Which of the following statements regarding freshwater ecosystems is false?
Species that rely on freshwater habitats are overrepresented on lists of at-risk species compared to terrestrial species.
The extinction rate of freshwater species is estimated to be three times higher than that of marine species and five times higher than that of terrestrial species.
Freshwater ecosystems account for about 6% of Earth’s surface, and about 1% of all described species rely on freshwater ecosystems for part or all of their life cycle.
Freshwater ecosystems provide valuable ecosystem services ranging from provision, regulation, and purification of fresh water to flood control and sediment transport.
The IUCN lists approximately one-third of all evaluated amphibian species as vulnerable, endangered, or critically endangered. Which of the following threats are thought to be responsible for the widespread amphibian decline?
Overharvest
Habitat destruction
Fungal disease
All of the above
Only 2.5% of all water on Earth is fresh water, as opposed to brackish or salt water. Most of this fresh water can be found in
lakes and rivers.
shallow aquifers, accessible for human use.
deep aquifers, inaccessible for human use.
glaciers or polar ice caps
Which of the following statements describing how global climate change is predicted to affect the supply of fresh water is false?
The volume of precipitation will decline uniformly across landmasses.
Rising sea level will increase the extent of saltwater intrusion in coastal rivers and aquifers.
Melting of mountain glaciers will cause increased flooding in the short term and water shortages in the long term.
Precipitation will increasingly come in the form of rain rather than snow, which will exacerbate flooding during the rainy season and water shortages during the dry season.
Besides blocking the movement of fish and invertebrates, dams harm ecosystems by
converting fast-flowing water into large lake-like habitats.
reducing the seasonal variability of stream flow.
flooding and thereby destroying riparian habitats.
All of the above
Which of the following would be considered a point source of water pollution?
Urban storm sewers
Runoff from agricultural fields
Effluent from a factory
Sedimentation due to logging
Strategies for restoring the natural flow patterns that many freshwater species rely on include
removing selected dams that produce minimal societal benefits at great ecological cost.
releasing water from dams to more closely resemble the natural timing and variability of stream flow.
removing levees to reconnect rivers to floodplains in select areas.
All of the above
Which of the following statements accurately describes how a freshwater PES (payments for ecosystem services) program might work?
End users pay upstream landowners to avoid logging and grazing practices that might otherwise reduce water quality.
End users pay a municipal water agency to filter and purify water for their use.
End users who pay for wells that tap deep into underground aquifers are exempt from municipal water use fees.
End users who reduce their water use earn tax breaks and other financial incentives.
Water use potentially could be reduced by adopting any of the following strategies except one. Which strategy would be unlikely to reduce water use?
Calculation of water footprints (the amount of water used throughout an item’s production chain)
Agricultural water pricing based on the number of hectares of farmed land rather than the actual amount of water used
Household water pricing that penalizes waste
Agricultural water pricing based on the amount of water used rather than the number of hectares farmed